1. Field of the Invention
The present invention relates to a delivery valve used in a compressor provided with a cylindrically shaped valve insertion space formed at a cylinder that partitions a compression space that communicates with the valve insertion space delivery ports and that also communicates with a delivery opening.
2. Description of the Related Art
Delivery valves in the prior art include the delivery valve used in a rotary compressor disclosed in Japanese Unexamined Utility Model Publication No. S56-109472, which is inserted in a round delivery hole that extends at a right angle to a plurality of delivery openings for discharging high pressure gas from the compression space, and is secured by a cylindrically shaped valve-holding fixture and a fastening member such as a rivet.
In addition, the delivery valve used in a movable vane type compressor disclosed in Japanese Unexamined Patent Publication No. S58-148293 is mounted within a cylindrically shaped delivery passage provided in a plurality of holes that pass through the external wall of the cylinder of the movable vane type compressor in the direction of the shaft while, at the same time, communicating with the compression space of the movable vane type compressor. It is held at both ends by a valve holder and it bends in an arc along the internal circumferential surfaces of the cylindrically shaped delivery passage to open and close the plurality of holes freely.
Moreover, the delivery valve used in a vane compressor disclosed in Japanese Unexamined Utility Model Publication No. S59-86389, is inserted into a rectangular parallelopiped delivery passage and is clamped and secured to the internal wall of the delivery passage by a retainer. The retainer holds and secures the delivery valve in close contact with the internal wall of the delivery passage, and is provided with lift restricting portions that restrict the lift quantity of the delivery valve.
Furthermore, the delivery valve used in a rotary compressor disclosed in Japanese Examined Utility Model Publication No. H7-8861 is housed within a valve chamber which is shaped roughly as a rectangular parallelopiped and is clamped and secured to the internal wall of the valve chamber by a valve holder. This valve holder comprises restricting portions that restrict the lift quantity of the delivery valve and a back plate that is inserted through a pair of grooved portions at the ends of the valve chamber, and the valve holder and the delivery valve are secured to each other by such means as screws.
However, in each of the examples cited above, the delivery valve is directly mounted in a valve chamber or in a valve insertion space formed at the cylinder, and thus the delivery valve directly opens and closes the delivery holes which open at the delivery chamber or the valve insertion space. As a result, a problem arises in that, due to the vibration of the delivery valve and the contact with the valve, the cylinder internal wall and, in particular, the seat surface, become deformed or damaged. If this happens, even if the delivery valve is replaced, the reliability of the seating characteristics of the delivery valve cannot be assured since the seat surface itself is deformed.